Vehicles with powertrains with multiple drive shafts where the respective drive shaft is driven by means of an electric drive device, where the axles lacks mechanical connection to each other are traditionally arranged to be electrically supplied via power electronics, the electric motor of the respective driving axle being supplied with a separate power electronics, where each driving axle is arranged to be controlled individually. Differences in speed between the shafts are handled by a superior control sending signals to the individually controlled shafts.
The fact that the shafts are not mechanically connected to each other implies in certain cases that the electric motors and the power electronics need to be increased in dimension. On a two-shaft loading vehicle where one shaft is in the air, the shaft being on the ground needs to be able to deliver the maximal driving power of the vehicle.
US2010133023 and WO2011138308 show examples of powertrains of vehicles where a common superior power electronic box controls electric motors of drive devices of drive shafts, where the power electronic box comprises double power electronic units where one power electronic unit is arranged to electrically supply an electric motor of a drive shaft with power electronics and another power electronic unit being arranged to electrically supply an electric motor of another drive shaft with power electronics.